A well bore device according to the present invention should be understood as different tools, equipment and/or instruments that are used in connection with oil relating work, in order to perform different operations.
In producing hydrocarbons, including water, oil and oil with entrained gas, from a geological formation, natural pressure in a reservoir acts to lift the produced medium upwards to a surface through a production tubing. The reservoir pressure must exceed the hydrostatic pressure of the fluid in the well bore and back-pressure imposed by the production facilities at the surface of the well to produce naturally. This is not always the case and one sometimes needs to assist the production flow to get it out of the production tubing.
For instance, if the natural pressure in the reservoir has dropped so much that the natural flow of liquid from the well has ceased or become too slow for economical production, artificial production methods are employed. Several artificial production systems and/or methods are known, where a fluid medium is injected into the production tubing. The fluid medium can be gas, liquid, processed well fluid or even a part of the well fluid from the reservoir. The two most commonly used systems today are water and gas injection.
In many cases, it is advantageous, at least during the first part of the artificial production period, to employ so-called Artificial gas lift. Natural gas, which is recovered from a reservoir, is treated and compressed, before it is rerouted and injected into a space (annulus) between a casing of the well and the production tubing and injected into the well fluid in the production tubing. As the well liquid in the production tubing becomes mixed with the injected natural gas, the density of the well liquid decreases, whereby the well liquid in the production tubing will be “lifted” towards the surface of the well.
The natural gas is injected through one or more gas lift valves arranged along the length of the production tubing, where the number of gas lift valves will depend on the needs in the field or well. The gas lift valves are usually arranged in side pocket mandrels forming a part of the production tubing, where a kick over tool is used to place and replace the gas lift valves in the side pocket mandrels.
From WO 98/26154 is known a kick over tool for use with a side pocket mandrel for positioning an elongated well tool instrument in an offset side pocket bore, where the kick over tool has a setting tool connected to a linkage mechanism normally held in a rigid straight line condition within a carrier housing. The kick over tool is orientated inside a side pocket mandrel and activated to pivotally extend the terminal end of the elongated well tool instrument into contact with the wall of a side pocket mandrel in vertical alignment with a side pocket bore. When the well tool instrument is lowered into the side pocket bore, the linkage mechanism is released from a straight line condition to align the well tool parallel to the carrier housing for insertion of the well tool in the side pocket bore. The well tool is released from the kick over tool when in the side pocket bore and the linkage mechanism is retracted into the carrier housing for retrieval.
U.S. Pat. No. 3,752,231 describes a flow control unit handling apparatus adapted for use in placing a flow control unit in a selected offset set in a well tubing mandrel and for removing said unit therefrom. An elongated housing adapted to support a flow control unit and pivotally connected at its upper end to a supporting means for raising and lowering the housing in the well tubing and an elongated protective guide means pivotally supported from the housing allowing the apparatus to pass freely downwardly through an offset mandrel. The apparatus also comprises a key for locating, positioning and tripping the apparatus into position to allow a valve to be placed or pulled from a selected offset seat.
However, due to the structure of known kick over tools, the kick over tool has to be retrieved from the production tubing after each performed operation, as the kick over tools are not designed to perform more than one operation at a time. This results in, for instance if a gas lift valve arranged in a side pocket mandrel should be replaced with a new gas lift valve, the kick over tool must first be run down the production tubing to retrieve the old gas lift valve, whereafter the kick over tool must be pulled out of the production tubing, the old gas lift valve removed, the new gas lift valve installed in the kick over tool and the kick over tool once again run down the production tubing, where the new gas lift valve is installed in the side pocket mandrel. As a result, it takes a lot longer to perform the desired operation and there is a greater chance that something may go wrong. Furthermore, in the known kick over tools, one disadvantage has been that the arms that hold the gas lift valve are not always able to align the gas lift valve with the side pocket bore of the side pocket mandrel, whereby the gas lift valve may be damaged during the installation in the side pocket bore.